LOCATION KOERLING           WA
Established Series
Rev. NCD/RJE
01/2002

KOERLING SERIES


The Koerling series consists of deep, well drained soils formed in outwash material with a component of volcanic ash and loess over lake sediments. Koerling soils are on terraces and have slopes of 0 to 65 percent. The average annual precipitation is about 17 inches and the mean annual temperature is about 46 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Vitrandic Haploxerepts

TYPICAL PEDON: Koerling ashy fine sandy loam, cultivated. (Colors are for dry soil unless otherwise noted.)

Ap--0 to 9 inches; grayish brown (10YR 5/2) ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium granular structure; slightly hard, very friable, slightly sticky; many roots; neutral (pH 6.8); abrupt smooth boundary. (4 to 10 inches thick)

Bwl--9 to 22 inches; pale brown (10YR 6/3) fine sandy loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky; many roots; common very fine pores; neutral (pH 7.2); gradual wavy boundary. (10 to 14 inches thick)

Bw2--22 to 40 inches; light brownish gray (2.5Y 6/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; few fine distinct mottles dark brown (10YR 3/3) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky; common fine roots; common very fine and fine pores; slightly alkaline (pH 7.8); clear wavy boundary. (10 to 20 inches thick)

2Bk--40 to 60 inches; light gray (2.5Y 7/2) silty clay loam, grayish brown (2.5Y 5/2) moist; massive with laminations; very hard, firm, sticky and plastic; few fine roots; few fine and very fine pores; dark brown organic or manganese coating on surface of plates; slightly effervescent; moderately alkaline (pH 8.4).

TYPE LOCATION: Stevens County, Washington; 240 feet west and 2,4l0 feet north of the southeast corner of sec. 29, T.36N., R.38E., W.M.

RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches ranges from 47 to 52 degrees F. These soils are usually moist but are dry in all parts between depths of 8 and 24 inches for 60 to 75 consecutive days in summer and autumn. The particle-size control section is 6 to 18 percent clay and more than 15 percent coarser than very fine sand and 0 to 15 percent coarse fragments. Depth to calcareous lake sediments lithologic discontinuity, ranges from 24 to 40 inches.

The A horizon has value of 5 or 6 dry, 3 or 4 moist and chroma of 2 or 3 dry or moist.

The Bw horizon has hue of 10YR or 2.5Y, value of 5 or 6 dry, 3 or 4 moist and chroma of 2 through 4 dry or moist. It is sandy loam or fine sandy loam. It is neutral or slightly alkaline.

The 2Bk horizon has hue of 10YR or 2.5Y, value of 5 through 7 dry, 4 through 6 moist and chroma of 1 through 3 dry or moist. It is sandy loam to silty clay loam. It is slightly alkaline or moderately alkaline.

COMPETING SERIES: These are the Arrastre, Barron, Bestrom, Cassolary, Clayton, Frailey, Green Bluff, Hudnut, Koseth, Quiden, Scala, Stoner and Tallowbox series. Arrastre and Bestrom soils are 20 to 40 inches deep to a lithic contact. Barron soils have a mean annual soil temperature of 54 to 56 degrees F. and are moderately acid in the B horizon. Cassolary soils are slightly acid or moderately acid in the solum. Clayton soils have a banded B horizon and lack carbonates in the lower part of the particle-size control section. Frailey, Hudnut, and Koseth soils are l5 to 35 percent rock fragments in the particle-size control section. Green Bluff soils lack carbonates and a lithologic discontinuity in the particle-size control section. Quiden soils are dry for 90 to l05 days and have a hue of 7.5YR or 5YR. Scala soils have a sola more than 40 inches thick and are not calcareous in any part of the particle-size control section. Stoner soils are dry for more than 90 days and are l5 to 35 percent rock fragments in the particle-size control section. Tallowbax soils are 20 to 40- inches deep to a paralithic contact.

GEOGRAPHIC SETTING: Koerling soil are on terraces at elevations of 1,500 to 2,000 feet. Slope is 0 to 65 percent. The soils formed in glacial outwash over stratified glacial lake sediments. They are in a continental climate; mean annual temperature is 46 degrees F.; average annual precipitation is 16 to 18 inches. The frost-free season is 110 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cedonia, Dart, Hunters, Marble and Phoebe soils. Cedonia and Hunters soils are fine-silty. Dart and Marble soils are sandy. Hunters and Phoebe soils have a mollic epipedon.

DRAINAGE AND PERMEABILITY: Well drained; slow or medium runoff; moderate permeability.

USE AND VEGETATION: These soils are used for range, woodland and cultivated areas are used for alfalfa, grass and small grains. Native vegetation is ponderosa pine, Douglas-fir, and western larch with an understory of creeping Oregon-grape, common snowberry, pinegrass, Idaho fescue, prairie junegrass, lupine, heartleaf arnica, white spirea and antelope bitterbrush.

DISTRIBUTION AND EXTENT: Northeastern Washington. Koerling series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Stevens County (Spokane Indian Reservation Area), Washington, 1970.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon from the mineral surface to 9 inches;
cambic horizon from 9 to 40 inches,
discontinuity to glacial lacustrine sediments with secondary lime at 40 inches.
The upper 9 inches is assumed to have a sum of the product of [1/2 Fe(ox) + Al(ox)] time 60 plus the volcanic glass of more than 30.


National Cooperative Soil Survey
U.S.A.